Washta, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 35.6 °F (low) to 58.9 °F (high). Annual precipitation averages 31.5 Inches. Washta is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 8.3 °F | 28.1 °F | 0.69 in. |
| February | 12.4 °F | 32.6 °F | 0.85 in. |
| March | 23.6 °F | 46.1 °F | 1.81 in. |
| April | 34.1 °F | 60.4 °F | 3.31 in. |
| May | 46.7 °F | 71.7 °F | 4.34 in. |
| June | 58.0 °F | 81.7 °F | 4.92 in. |
| July | 61.3 °F | 84.2 °F | 3.82 in. |
| August | 58.9 °F | 82.0 °F | 4.22 in. |
| September | 49.6 °F | 76.7 °F | 2.92 in. |
| October | 36.6 °F | 63.4 °F | 2.21 in. |
| November | 23.9 °F | 46.7 °F | 1.4 in. |
| December | 13.8 °F | 33.2 °F | 1.0 in. |
| Annual | 35.6 °F | 58.9 °F | 31.49 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |